package com.yida.common.core.utils.sign;

import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

import javax.crypto.Cipher;

/**
 * RSA加密解密
 * 
 * @author yida
 **/
public class RsaUtils {
	// Rsa 私钥
    public static String privateKey = "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";

    /**
     * 私钥解密
     *
     * @param privateKeyString 私钥
     * @param text 待解密的文本
     * @return 解密后的文本
     */
    public static String decryptByPrivateKey(String text) throws Exception
    {
        return decryptByPrivateKey(privateKey, text);
    }

    /**
     * 公钥解密
     *
     * @param publicKeyString 公钥
     * @param text 待解密的信息
     * @return 解密后的文本
     */
    public static String decryptByPublicKey(String publicKeyString, String text) throws Exception
    {
        X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(Base64.decode(publicKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, publicKey);
        byte[] result = cipher.doFinal(Base64.decode(text));
        return new String(result);
    }

    /**
     * 私钥加密
     *
     * @param privateKeyString 私钥
     * @param text 待加密的信息
     * @return 加密后的文本
     */
    public static String encryptByPrivateKey(String privateKeyString, String text) throws Exception
    {
        PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(Base64.decode(privateKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, privateKey);
        byte[] result = cipher.doFinal(text.getBytes());
        return Base64.encode(result);
    }

    /**
     * 私钥解密
     *
     * @param privateKeyString 私钥
     * @param text 待解密的文本
     * @return 解密后的文本
     */
    public static String decryptByPrivateKey(String privateKeyString, String text) throws Exception
    {
        PKCS8EncodedKeySpec pkcs8EncodedKeySpec5 = new PKCS8EncodedKeySpec(Base64.decode(privateKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec5);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
        byte[] result = cipher.doFinal(Base64.decode(text));
        return new String(result);
    }

    /**
     * 公钥加密
     *
     * @param publicKeyString 公钥
     * @param text 待加密的文本
     * @return 加密后的文本
     */
    public static String encryptByPublicKey(String publicKeyString, String text) throws Exception
    {
        X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(Base64.decode(publicKeyString));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec2);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        byte[] result = cipher.doFinal(text.getBytes());
        return Base64.encode(result);
    }

    /**
     * 构建RSA密钥对
     *
     * @return 生成后的公私钥信息
     */
    public static RsaKeyPair generateKeyPair() throws NoSuchAlgorithmException
    {
        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
        keyPairGenerator.initialize(1024);
        KeyPair keyPair = keyPairGenerator.generateKeyPair();
        RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
        RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
        String publicKeyString = Base64.encode(rsaPublicKey.getEncoded());
        String privateKeyString = Base64.encode(rsaPrivateKey.getEncoded());
        return new RsaKeyPair(publicKeyString, privateKeyString);
    }

    /**
     * RSA密钥对对象
     */
    public static class RsaKeyPair
    {
        private final String publicKey;
        private final String privateKey;

        public RsaKeyPair(String publicKey, String privateKey)
        {
            this.publicKey = publicKey;
            this.privateKey = privateKey;
        }

        public String getPublicKey()
        {
            return publicKey;
        }

        public String getPrivateKey()
        {
            return privateKey;
        }
    }
    
    public static void main(String[] args) throws NoSuchAlgorithmException {
    	RsaKeyPair rsaKeyPair = generateKeyPair();
    	System.out.println("私钥："+rsaKeyPair.getPrivateKey());
    	System.out.println("公钥："+rsaKeyPair.getPublicKey());
	}
    
}
